Polymers and copolymers of, and surgical devices made from lactide and/or glycolide and/or related compounds are well-know. See, e.g., U.S. Pat. Nos. 2,668,162, 2,683,136, 2,703,316, 2,758,987, 3,225,766, 3,268,486, 3,268,487, 3,297,033, 3,422,181, 3,442,871, 3,463,158, 3,468,853, 3,531,561, 3,565,869, 3,597,449, 3,620,218, 3,626,948, 3,636,956, 3,736,646, 3,739,773, 3,772,420, 3,733,919, 3,781,349, 3,784,585, 3,792,010, 3,797,499, 3,839,297, 3,846,382, 3,867,190, 3,987,937, 3,878,284, 3,896,802, 3,902,497, 3,937,223, 3,982,543, 4,033,938, 4,045,418, 4,057,537, 4,060,089, 4,137,921, 4,157,437, 4,243,775, 4,246,904, 4,273,920, 4,275,813, 4,279,249, 4,300,565, and 4,744,365, U.K. Pat. or Appln. Nos. 779,291, 1,332,505, 1,414,600 and 2,102,827, D. K. Gilding et al., "Biodegradable polymers for use in surgery-polyglycolic/poly (lactic acid) homo-and copolymers: 1," Polymer, Volume 20, pages 1459-1464 (1979), and D. F. Williams (ed.) Biocompatibility Of Clinical Implant Materials, Volume II, chapter 9: "Biodegradable Polymers" (1981).
Surgical devices prepared from copolymers containing dioxanone and lactide are known in the art.
U.S. Pat. No. 4,052,988 describes random copolymers containing dioxanone and up to 50 percent by weight of other copolymerizable monomers which produce non-toxic and absorbable copolymers.
U.S. Pat. No. 4,643,191 describes copolymers of dioxanone and lactide fabricated by initially polymerizing dioxanone monomer to form a mixture of dioxanone homopolymer and dioxanone monomer, adding lactide monomer to the mixture, and subsequently polymerizing. The '191 patent does not describe copolymers fabricated by the random polymerization of lactide and dioxanone.
As described above, bioabsorbable sutures are known in the art. A desirable characteristic of a bioabsorbable suture is its ability to exhibit and maintain desired tensile properties for a predetermined time period followed by rapid absorption of the suture mass (hereinafter "mass loss".)
Absorbable multifilament sutures such as Dexon, Vicryl, and Polysorb commercially available from Davis & Geck (Danbury, Conn.), Ethicon, Inc. (Sommerville, N.J.), and United States Surgical Corporation (Norwalk, Conn., respectively, are known in the industry as short term absorbable sutures. The classification short term absorbable sutures generally refers to surgical sutures which retain about 20 percent of their original strength at three weeks after implantation, with the suture mass being essentially absorbed in the body within about 60 to 90 days post implantation.
Long term absorbable sutures are generally known to be sutures which retain about 20 percent of their original strength at six or more weeks after implantation, with the suture mass being essentially absorbed in the body Within about 180 days post implantation. For example, PDS II, a synthetic absorbable monofilament suture, commercially available from Ethicon, Inc. (Sommerville, N.J.), retains about 20 to about 30 percent of its original strength at six weeks after implantation. However, PDS II exhibits minimal mass loss until 90 days after implantation with the suture mass being essentially absorbed in the body about 180 days after implantation. Maxon, commercially available from Davis & Geck (Danbury, Conn.) is another absorbable synthetic monofilament generally fitting this absorption profile.
Therefore, it would be advantageous to provide a long term bioabsorbable synthetic monofilament surgical suture which exhibits and maintains tensile properties and handling characteristics comparable to PDS II, while having a shorter and thus improved mass loss profile.